The embodiments of the present invention relate to vehicle suspension control systems and, more specifically, to a vehicle suspension control system adaptable to predicted and actual abnormal road conditions.
Passenger vehicles are designed to drive on a variety of road surfaces and geometric conditions. Occasionally, a vehicle encounters exceptional (abnormal) road conditions, such as debris, severe potholes, bumps and the like. Adaptive or active suspension systems enable selective adjustment of the suspension characteristics such as damping and stiffness, responsive to the contact between the vehicle wheels and the abnormal road feature. This helps improve the vehicle's ride comfort, handling, and safety.
However, in order for conventional active suspensions to operate the actuatable elements of the suspension system responsive to the abnormal road feature, the vehicle wheels must contact the road feature. Due to the need to interact with the abnormal road feature prior to operating the actuatable suspension elements, the system response may not be as timely and effective as it might otherwise be, because of factors such as the dynamic response times of the system as a whole and the individual system elements, and the speed of the vehicle.
Certain vehicle design parameters may also be tailored to mitigate the effects of interaction between the vehicle and abnormal road features. For example, providing a vehicle with a relatively higher ground clearance reduces its susceptibility to damage due to many bumps in the road or debris located on the road surface. However, a vehicle with higher ground clearance may have a relatively greater fuel consumption than a vehicle with a smaller ground clearance.
In view of the above, it is desirable to incorporate an adaptive or active suspension system into the vehicle to enable selective adjustment of characteristics such as suspension stiffness and damping responsive to abnormal road conditions. It is also desirable to have advance notice of the type and severity of any abnormal road or driving conditions so that actuatable elements of a vehicle control system can be actuated in real time to help mitigate the undesirable consequences of driving over the abnormal surfaces, if necessary before the vehicle wheels encounter the abnormal road condition.
Thus, it is desirable to detect an abnormal road condition, predict the severity of the condition, and operate actuatable elements of the suspension system in response to the predicted type and severity of the abnormal road condition. For efficiency, it is also desirable that the suspension control system operates the actuatable system elements only for the length of time (and only to the degree) needed to mitigate the deleterious effects of a particular abnormal road condition.